Attachment plug cap



' Invent or George B .Br"|ancle1",

G. B. BENANDER ATTACHMENT PLUG CAP Filed oot'. 15, .1952

Hi5 Attorney Patented Feb. 26, 1935 UNITED STATES PATENT OFFICE mimics car I Y I George B. Benander,

Yalecville, Coma, asaignor to The Monowatt Electric poratlon of Connecticut Corporation, a cor- Application October 15, 1932, Serial No. 637,977

7 LClaim- (Cl. 173-461) The present invention relates to attachment plug caps such as are used for connecting an electrical conductor .to. a plug receptacle and especially to attachment plug caps of the type intended to forma part of a cord set, it being understood that by a cord set is meant a length of cord having a plug cap permanently attached to it at one end, the other end of the cord being attached to or adapted to be attached to some other wiring device. In the manufacture of cord sets, one end of the conductor cord length is permanently attached to the plug cap at the factory.

One object of my invention is to provide an improved construction and arrangement of plug cap which can be manufactured at low cost and wherein. the cord is attached to it during the assembling of the contact blades in the"base.

A further object oi my invention is to provide an improved method of assembling a plug cap with the conductor ends attached thereto.

For a consideration of what I believe to be 7 novel and my invention, attention is directed to the following specification and the claim appended thereto.

In the drawing, Fig. l is an exploded perspec-' tive view of a plug cap embodying my invention; Fig. 2 is a perspective view of a plug cap showing the contacts attached to the'base or body and the conductor connected to the con tacts, and Fig. 3 is a transverse sectional view of the construction shown in Fig. 2.

. Referring to the drawing, 1 indicates the base or body of the cap which may be molded from suitable insulating material, and 2 and 3 indicate the two contacts carried by the base. Contacts 2 and 3 may be brass or other suitable conducting material and may be formed by a punching operation.

Base 1 has a central opening 4 for the passage of the conductor. Inside the base on'opposite sides of opening 4,-the wall of the base isthickened to provide fiat seats or surfaces .5 in which are spaced openings 6.

Contacts 2 and 3 are alike. Each comprises a prong '7, a foot 8 which extends at right angles .to prong l, and two spaced projecting fingers 9 which are attached to the outer edge of foot 8 and have serrated or roughened edges 10. Formed integral with foot 8 directly adjacent to prong '1 are two clamping lugs 11 adaptedto be bent down from the position shown in Fig. 1 to the position shown in Figs. 2 and 3, wherein they clamp the wires 12 of the conductor 13. Fingers 9 fit into openings 6 and are held therein by frictional engagement, the roughened or serrated edges biting into the material of the base.- Foot 8 rests against seats 5.

In assembling the construction, the end of conductor 13 is passed through opening 4 as shown in Fig. 1, after which the ends of the .wires 12 from which the insulation has been re moved are placed under the clamping lugs 11. As shown clearly in Fig. 2, the wire is placed under one lu then extended back of contact prong '7 and around to the front of it and under the other lug. The lugs are bent down on the wires as shown in Figs. 2 and 3 to firmly connect'the wires to the contacts and the fingers 9 on the contacts are forced into the openings 6. The operations of bending down the lugs 11 and forcing the fingers 9 into opening 6 may be performed as a single operation. To this end, the

base 1 may be located in a suitable fixed support and the contacts may be mounted in a suitable fixture adapted to be moved downward relatlvely to the support and the base. The contacts are placed in the fixture, the ends of the wires placed under the lugs 11 after the manner already explained, after which the fixture is actuated to force the fingers 9 into opening 6 and at the same time press down the lugs 11. This is a simple operation which can be quickly carried out at low labor cost in that the work maybe performed by relatively unskilled help. At the same time, a firm and satisfactory connection is established between the wiresand the contacts and between the contacts and the base.

It will be noted that lugs 11 are bent outwardly to overlie the feet and that the wires are passed across the surfaces. of the prongs adjacent to opening 4. By this arrangement, the lugs when bent down clamp the conductors directly against the top faces of the feet and draw them tightly against the prongs, thus providing goodelectrical tions.

.By providing two spaced fingers 9 which enand mechanical connecgage spaced openings in the base, I obtain anrm 5 Letters Patent oi the United States is:

A plug cap comprising a base having a cen-= tral opening for the passage of conductors and fiat seats on opposite sides of the opening and directly adjacent thereto, contacts each having 10 a foot which rests on one of said flat seats and .9, prong which projects outwerdly from the foot menace at the side ofthe foot adjacent to said opening, means fastening the contacts to the base, and clamping lugs integral with each of said feet on opposite sides of each prong directly at the bases of the prongs bent outwardly to overlie the respective foot for clamping conductors to the contacts, whereby conductors may be extended under the lugs and across the surfaces of the prongs adjacent to said openings. 

